apart from that: can there be so many improvements to mp shooters? other than graphic updates? I haven't played UT 3, but from what I heard and read, little was changes, weapons mostly stayed, modes mostly stayed. the last great innovation was the inclusion of vehicles in the last one (which imo was very well done). I could go on for a bit, but I think I made my point. if, of course, the two companies could create some kind of discussion and debate on how the game could be on a conceptual level. I guess SD as a publisher would be more willing to accept unorthodox, new ideas, which can make the game a great success.
The ideal improvements for the sequel to a successful online multiplayer FPS game would be to keep the winning formula (keep the feel of the game play and the weapons and game types the same) while improving the graphics, the netcoding, the cheat protection, the server administration, the server browser, and the user interface while perhaps offering up high quality new maps and new game types.
From the perspective of a devoted fan of an older FPS game, one of the crucial key improvements is that the game gets put back on store shelves, it gets marketed, people buy it, and throngs of people who are new to the franchise come online, increasing online player counts and bringing new people into the community. After all, a fan of the original who plays the game to this day is happy to keep playing the older game but craves having a larger community of people to play it with. For example, I'd love to play UT99 DOMination but the game no longer has a sufficient player base to support that game type at all. (This is similar to Sins's problem; Sins doesn't have a large enough online multiplayer community to have clans or to have enough people who take the game seriously enough that they'd be willing to download, install, and play custom maps and mods online). I'd also like to play regular weapons Capture-the-Flag on populated public servers that host an assortment of custom maps but most of the servers are now either Instagib or all-Sniper Rifles. (I do play a lot of UT99 regular weapons CTF, but it's in the form of clan-match style 5-on-5 organized pickup games matches, which are a tremendous amount of fun--if there are any UT99 CTF players reading this, just ask and I can hook you up.)
UT3 failed miserably on all of these counts except maybe for netcoding and graphics.
Ideally, a UT4 would be a bona-fide UT99-2 but with modern graphics, the best of the newer game types (Onslaught, Invasion, Bombing Run, Vehicle CTF) in addition to the original game types (Deathmatch, Team DM, CTF, Domination, and Assault) and a superb user interface and server browser.